/*
 * Copyright (C) 2008 Esmertec AG.
 * Copyright (C) 2008 The Android Open Source Project
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package com.android.mms.model;

import java.util.ArrayList;

public class Model {
	protected ArrayList<IModelChangedObserver> mModelChangedObservers = new ArrayList<IModelChangedObserver>();

	public void registerModelChangedObserver(IModelChangedObserver observer) {
		if (!mModelChangedObservers.contains(observer)) {
			mModelChangedObservers.add(observer);
			registerModelChangedObserverInDescendants(observer);
		}
	}

	public void unregisterModelChangedObserver(IModelChangedObserver observer) {
		mModelChangedObservers.remove(observer);
		unregisterModelChangedObserverInDescendants(observer);
	}

	public void unregisterAllModelChangedObservers() {
		unregisterAllModelChangedObserversInDescendants();
		mModelChangedObservers.clear();
	}

	protected void notifyModelChanged(boolean dataChanged) {
		for (IModelChangedObserver observer : mModelChangedObservers) {
			observer.onModelChanged(this, dataChanged);
		}
	}

	protected void registerModelChangedObserverInDescendants(IModelChangedObserver observer) {
		// Dummy method.
	}

	protected void unregisterModelChangedObserverInDescendants(IModelChangedObserver observer) {
		// Dummy method.
	}

	protected void unregisterAllModelChangedObserversInDescendants() {
		// Dummy method.
	}
}